The name Lucas is a boy's name of Greek, Latin origin meaning "man from Lucania"

The surname Kelly in Ireland is derived from O'Ceallaigh, which is based on the popular personal name Ceallach, meaning either 'bright headed' or 'troublesome'. The O'Ceallaighs were a native Gaelic sept located in Counties Galway, Meath, Wicklow, Antrim and Sligo.